The present invention relates to power tools in general and, more particularly, to power cutting tools having cutting elements. The invention is especially useful in saber saws having reciprocating cutting blades.
It is known for one skilled in the art of saber or jig saws to hold the housing with one hand, either with or without the aid of an extension handle, and to place the other hand on a detachably-mounted guide handle. The guide handle is generally positioned on the upper portion of the housing above the cutting blade so that one can simultaneously guide the cutting blade and exert downward pressure on the housing so as to prevent the power tool from wandering away from the desired cutting position.
The guide handles which are known in the art are formed with a head portion constituted of synthetic plastic material and a metallic elongated shaft portion which, in the region of its free end, is provided with an outer thread. In other words, in order to mount the guide handle on the housing, the guide handle must be screwed into a corresponding internal thread which is formed in the housing of the power tool.
However, these known handles have not proven to be altogether satisfactory in use. First of all, the prior art guide handles have the drawback that a user cannot easily guide the cutting blade to follow a predetermined cutting path. Since the guide handles are screwed into the housing, if one wishes to follow a curvilinear cutting path, then one must repeatedly loosen the handle counterclockwise and then pivot the housing relative to the handle. This is particularly inconvenient if one has to cut out a complex geometrical pattern. A user frequently will not bother with repeatedly unthreading the screw from the housing, thus relying solely on the strength of his arm to follow the desired cutting path, thereby making the cutting operation rather inaccurate and uneven.
Secondly, the metallic shaft portion of the prior art guide handles has the drawback that it conducts heat towards the hand of a user. The amount of heat generated by the motor contained within the housing and by the reciprocating cutting blade can be of a considerable magnitude if a cutting takes a long amount of time and/or if the material to be cut is possessed of a high resistance to cutting.
Finally, the prior art guide handles have the further disadvantage that they are especially difficult to remove when the power tools is to be used in a cramped environment. Where spatial requirements are limited, it is very inconvenient for a user to repeatedly unscrew the guide handle from the housing.